SiC Film Growth Nozzle Integrity via Chlorine Gas
Solution Overview
Problem
The challenge in semiconductor device manufacturing is the decomposition of silicon (Si) source gas in gas supply nozzles and subsequent deposition of Si on the nozzle walls during the growth of silicon carbide (SiC) epitaxial films in vertical substrate processing apparatuses, leading to inefficient gas supply and contamination issues.
Innovation Solution
A method involving a substrate processing apparatus with a gas supply system that includes a first gas supply unit to deliver a silicon-containing gas and a chlorine-containing gas parallel to the substrate surfaces, a second gas supply unit to provide a reducing gas, and an option for a third gas supply unit to supply a carbon-containing gas, which helps in suppressing the decomposition of Si source gas and deposition of Si within the nozzle.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Productivity
If a vertical substrate processing apparatus is used to process multiple substrates at once, then productivity is improved, but Si source gas decomposes in the gas supply nozzle and deposits on the nozzle walls
Solution Approach 1:
The patent changes the chemical parameters of the gas supply system by introducing a chlorine-containing gas (such as HCl) mixed with the Si source gas. This chemical parameter change prevents Si deposition in the gas supply nozzle by forming volatile Si-Cl compounds, thereby maintaining nozzle integrity while enabling vertical batch processing of multiple substrates
Solution Approach 2:
The patent introduces a chlorine-containing gas as an intermediary substance that mediates between the Si source gas and the nozzle walls. This intermediary prevents direct decomposition and deposition of Si on the nozzle by forming intermediate Si-Cl species that remain in the gas phase, thus protecting the nozzle while allowing high-productivity vertical processing
2Productivity
If Si source gas is supplied at high temperature for SiC film growth, then film formation rate is improved, but Si decomposes and deposits on the gas supply nozzle
Solution Approach 1:
The patent converts the harmful high-temperature decomposition of Si source gas into a beneficial process by introducing chlorine-containing gas. The high temperature that would normally cause Si deposition now facilitates the formation of volatile Si-Cl compounds, which can be transported to the substrate without depositing on the nozzle, thus converting a harmful effect into a beneficial one
Solution Approach 2:
The patent changes the chemical composition parameter of the gas mixture by adding chlorine-containing gas, which fundamentally alters the thermal behavior of the Si source gas. This parameter change allows the system to operate at high temperatures needed for fast film formation while preventing Si deposition through chemical modification of the gas phase species
3Manufacturing precision
If Si source gas is supplied to the reaction chamber, then SiC film growth is achieved, but Si deposits on the inner wall of the gas supply nozzle
Solution Approach 1:
The patent introduces chlorine-containing gas as an intermediary that prevents Si from depositing on the nozzle walls while still delivering Si to the substrate for film growth. The intermediary forms transient Si-Cl species in the gas phase that prevent unwanted deposition but allow controlled delivery of Si to the reaction chamber
Solution Approach 2:
The patent changes the chemical parameters of the gas supply system by introducing chlorine, which fundamentally alters the deposition behavior of Si. This parameter change reduces Si loss in the nozzle by forming volatile Si-Cl compounds while maintaining or improving SiC film quality through controlled Si delivery to the reaction chamber
Applied Scientific Principles
This section explains which scientific principles are used to turn an abstract innovation direction into a practical engineering solution.
Function Achieved in This Case
This approach prevents Si source gas decomposition and deposition within the gas supply nozzle, ensuring stable and uniform SiC film growth, improving substrate processing quality and reducing production costs by maintaining nozzle integrity and enhancing film thickness uniformity.
Implementation Method 1
forming silicon carbide films on the substrates by supplying at least a silicon-containing gas and a chlorine-containing gas or at least a gas containing silicon and chlorine into the reaction chamber
Implementation Method 2
supplying at least a reducing gas into the reaction chamber from a second gas supply outlet of a second gas supply unit
Data Source
AI summary
Provided is a substrate processing apparatus, a semiconductor device manufacturing method, and a substrate manufacturing method. The substrate processing apparatus comprises: a reaction chamber configured to process substrates; a first gas supply system configured to supply at least a silicon-containing gas and a chlorine-containing gas or at least a gas containing silicon and chlorine; a first gas supply unit connected to the first gas supply system; a second gas supply system configured to supply at least a reducing gas; a second gas supply unit connected to the second gas supply system; a third gas supply system configured to supply at least a carbon-containing gas and connected to at least one of the first gas supply unit and the second gas supply unit; and a control unit configured to control the first to third gas supply systems.